320 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 13 



This protection is enhanced by the highly gregarious nature of the plant, 

 which is indicated by the fact that isolated plants rarely reach the height 

 of those in dense colonies. 



The desiccating effect of wind on the Channel Islands is great enough 

 to affect some of the plants which, in the interior of the mainland, 

 would normally be shrubs. There is, on the islands, a distinct tendency 

 for the tips of the upper branches to die back during the dry season. 

 This condition is noted in the insular varieties of Lotus scoparius, L. 

 Dendroideus, L. Traskiae, and L. Veatchii. Rubus vitifolius, Holodiscus 

 discolor, and Sambucus coerulea also show this same tendency. 



Properly included in the group of suffrutescent plants may be certain 

 low, evergreen herbs (Raunkiaer, 1934), such as A triplex calif ornica, 

 Atriplex leucophylla. Astragalus Nevinii, A. Traskiae, Frankenia grand- 

 ifolia, Heliotropiujn Curassavicum oculatum, and Heuchera rnaxina. In 

 addition to these there are many other suffrutescents, both on the islands 

 and the mainland. Again, several of the introduced plants are suffru- 

 tescents. Since these last two groups of plants owe their habits to the 

 Mediterranean climate and not primarily to their insular environment 

 they will not be listed at this time. 



Suffrutescent plants are especially prevalent in many parts of the 

 Mediterranean region, according to Raunkiaer (1934), and have an 

 important place in his floristic spectrum for that region. Suffrutescents, 

 in addition to those previously mentioned, occurring in areas of mari- 

 time climate include the following : 



Suaeda californica Grindelia rubricaulis 



var. pubescens var. robusta 



Mirabilis laevis var. latifolia 



var. cedrosensis var. platyphlla 



var. cordifolia Corethrogyne filaginifolia 



Spergularia macrotheca var. virgata 



var. Talinum var. robusta 



Heuchera maxima var. incana 



Lupinus longiflorus var. latifolia 



L. arboreus Hemizonia clementina 



L. Chamissonis Encelia californica 



L. albifrons Eriophyllum confertiflorum 



var. Douglasii var. trifidum 



Erysimum insular e Malacothrix saxatilis 



Cryptantha maritima var. tenuifolia 



Galium catalinense var. implicata 



G. Nuttallii M. Blairii 



